Candida gut colonization, yeast species distribution, and biofilm production in Clostridioides difficile infected patients: a comparison between three populations in two different time periods.

Candida gut colonization and yeast biofilm production capacity were investigated, by means of XTT reduction assay, in Clostridioides difficile infected (CDI) patients, in non-CDI diarrheic patients, and in healthy donors in two different time periods (2013-2015 and 2018-2019 respectively). Candida gut colonization was significantly (p < 0.001) associated to C. difficile infection, and to patients infected with hypervirulent C. difficile strains bearing the tcdC deletion at nucleotide 117 (p = 0.0003). Although there was not a prevalent yeast species in CDI patients, C. albicans was the species significantly (p < 0.001) associated to both the infections sustained by the non-hypervirulent C. difficile strains and those caused by the hypervirulent strain (p = 0.001). The biofilm production by the yeasts isolated from the CDI patients and from non-CDI diarrheic patients did not differ significantly. However, a significantly (p = 0.007) higher biofilm production was observed in the Candida strains, particularly C. albicans, isolated from healthy donors compared to that of the yeasts cultured from CDI patients. Seasonal occurrence was observed in the isolation rate of CDI and non-CDI diarrheic cases (p = 0.0019), peaking in winter for CDI patients and in spring for non-CDI diarrheic patients. Furthermore, seasonality emerged in the gut colonization by Candida of CDI patients in the winter. It seems, therefore, that the reduced capacity of biofilm production by Candida strains isolated from CDI patients might have a role in the development of C. difficile infection, probably facilitating the spread of the bacteria into the gut thus amplifying their pathogenic action.

Dietary habits and growth: an urban/rural comparison in the Andean region of Apurimac, Peru.

INTRODUCTION: The efficacy of interventions against children malnutrition crucially depends on a myriad of factors other than the simple food intake, that must be carefully studied in order to plan a balanced policy. The relation between dietary patterns and growth is at the very heart of the problem, especially in consideration of the fact that dietary pattern involves dimension other than pure caloric intake in its definition. In this work we investigated the relations between dietary pattern and growth comparing children from a rural and a urban area in Andean Peru, in terms of food habits and anthropometric variables to develop a model usable in context interventions against malnutrition. MATERIAL AND METHODS: A sample of 159 children (80 from urban, 79 from rural area), aged from 4 to 120 months (72.7 ± 37.5 SD) was collected. The data were investigated by a multidimensional (principal component analysis followed by inferential approach) analysis to correlate the different hidden dimensions of both anthropometric and dietary observables. The correlation between these dimensions (in the form of principal components) were computed and contrasted with the effects of age and urban/rural environments. RESULTS: Caloric intake and growth were not linearly correlated in our data set. Moreover urban and rural environment were demonstrated to show very different patterns of both dietary and anthropometric variables pointing to the marked effect of dietary habits and demographic composition of the analyzed populations. The relation between malnutrition and overweight was at the same time demonstrated to follow a strict area-dependent distribution. DISCUSSION AND CONCLUSION: We gave a proof-of-concept of the non-linear character of the relation between malnutrition (in terms of caloric intake) and growth, pointing to the need to calibrate interventions on food pattern and not only quantity to contrast malnutrition effects on growth. The education toward a balanced diet must go hand-in-hand with the intervention on caloric intake in order to prevent effects on health.